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entire head. Thus, out of eighty-three herrings, only fifteen had the heads to them, though the proportion of the one to the other was different at different nests. The heads when thus absent are entirely so—that is to say, they are not to be found lying about separately. That the chick should eat the head of the herring by preference seems unlikely, and particularly when it is quite young. Yet I have seen four herrings lying about a newly-hatched chick, which were quite fresh and almost untouched, but headless. The question, therefore, arises whether the parent-bird eats the head after disgorging the whole fish, or whether, in the majority of cases, it is disgorged minus the head. Fish are, I believe, always swallowed by birds which prey upon them, head first, and would therefore, one would suppose, lie in the gullet in this direction. If disgorged again tail first, as they lay, the gills, by expanding, might offer such resistance that the head would be in most cases torn off. If this be so, then the skua may often receive the fish headless from the gull, or, if otherwise, the head would be still more likely to be torn off, on a second disgorgement. This, however, one would think, must be a very disagreeable process for the bird disgorging, and it would seem more probable that the fish can be turned or shifted in the gullet, by some muscular action on its part, so as to be brought up head foremost, as it descended; but whether there is any evidence as to this, I do not know. If the head of the herring does not remain in the gullet, then it must be eaten by the parent skuas after ejection, and it would seem that they looked upon this portion as their peculium, to which